


Unwind

by RockSaltandCherryPie



Category: Supernatural
Genre: Bottom!Sam, M/M, Sassy, Sastiel - Freeform, Top!Cas, bunker!sex
Language: English
Status: Completed
Published: 2014-01-27
Updated: 2014-01-27
Packaged: 2018-01-10 05:24:56
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,275
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1155621
Author URL: https://archiveofourown.org/users/RockSaltandCherryPie/pseuds/RockSaltandCherryPie
Summary: <blockquote class="userstuff">
              <p>Something that could have happened after 9x11?</p>
            </blockquote>





	Unwind

**Author's Note:**

> Takes place the night of 9x11, so spoilers for 9x11
> 
> For the record, Wincest is my OTP & this is my first time writing Sastiel or even venturing onto this ship. (My sister encouraged me to write this ficlet after I texted her some sastiel!smut) It was very interesting and enjoyable, I must say. ;)  
> (Also, angsty!Sam is the best Sam)

It all happened way too fast. But Sam wasn’t really thinking straight today anyway and Cas, well… do angels even have a concept of a straight frame of mind? It had been made pretty clear on numerous occasions that humans and angels have hardly anything in common. But tonight Castiel admitted something to Sam about his time as a human and Sam was reminded then that Cas wasn’t just any angel. Not to mention he had been their friend and a great alliance to him and Dean for years now. It was hard to believe he was the same species as the ruthless comet that he had been chained to for weeks, who killed so many innocent people. Including Kevin. But it had been Sam’s skin Gadreel was wearing. _His_ face was the last one Kevin saw before he died. And what about Dean? Always willing to take the blame for everything, say it was _his_ fault Kevin’s insides were fried.

So yeah. Sam wasn’t thinking clearly. At least in terms of caring and not caring about consequences.

So when he invaded Cas’ personal space, pressed his body against his just a little too persistently, his rational thoughts were somewhere else. Cas responded immediately. Sam felt hesitant hands come around his body to rest on his hips.

“Sam… What are you doing?” Cas’ deep voice was soft, shaky. And Sam liked the sound of it, liked the way Cas leaned in slightly to press their foreheads together. Liked the heat of his body amidst the dampness of the underground bunker. Sam didn’t really want to talk. Words somehow made all of this more real. Hugging Cas was one thing, but this… the way he listened to Cas’ breathing pick up as he bumped his leg in between his thighs, the way he could _feel_ Cas’ body responding to his… well this was something else entirely. And it’s not like just because this is the first time anything like this has ever happened between them, Sam never _thought_ about it…

Oh my god, if Dean could see him now. His hand slithering up underneath that heavy trench coat that Cas was back to wearing, wanting this, _needing_ this… Whatever, Dean wasn’t here… Dean made a choice – hell, Dean made a choice _for_ him, so he could say fuck all about _this_ choice. A choice he was making all on his own, thank you very much.

If Sam’s mind was loud his actions were even louder, as if they were at odds with each other. The two of them gravitated toward the bedroom, Sam guiding Cas by enclosing his hands over Cas' that were already on his hips, intent on not breaking the boundary they had clearly already crossed: the boundary between friendly touches and, well, a little bit more than friendly touches.

"Sam..." Cas began to shake his head as he started to comprehend what was going on here.

"It's okay," Sam reassured him, so soft it was almost a whisper, as he pulled their bodies together again. Their hips slotted together and Sam's eyes wandered down, not only feeling the thick bulge at Cas' groin but also seeing it. It was too quiet in the room, the high-pitched hum of the achromatic lights overhead too deafening. It might have been angels voicing their protest.

Sam was fairly certain Cas knew how to use his body for sex; after all, during his time as a human he had told Sam and Dean that his "time with April was very educational," but it was no secret that the angel was hesitant now. But then Sam's hands came up to cup Cas' neck and he encouraged him with a whispered "touch me" between unsteady exhales. Slowly, Cas liberated himself from the confinement of the trench coat, shrugging his shoulders out of it and letting it fall to the floor. His hands slid up Sam's waist, silently mapping out every inch, every slight contour through the fabric.

Sam reciprocated the movement, wandering hands pushing Cas' shirt up from where it was neatly tucked into his pants. Skin on skin now, the overwhelming sensation of another body's heat right under his fingertips cracked something within Sam's senses and he picked up the pace of his movements. There would be absolutely no turning back now. No forgetting this.

Cas uttered a few grunts but mostly he just shut his eyes, feeling Sam's pliant body in his arms, apparently still searching for the right thing to do or say. They didn't kiss yet, that somehow seemed too intimate. But when Sam popped open the button on Cas' pants and tore down the zipper, Cas made no move to stop him. Sam dropped his head to Cas' shoulder and pressed a firm palm over the hard line of Cas' cock through his boxers. A piercing _crack_ followed by a series of hisses exploded overhead and they were instantly in complete darkness. Sam's heart skipped a beat and he blinked around, trying to get his eyes to focus, until a single backup bulb flickered on somewhere above them, glowing blue and struggling to combat the blackness. And it was like the dark was an added shield from the cruel gaze of reality because Sam felt more comforted than ever. Not to mention the high-pitched whine was finally silenced.

"Sorry..." Cas started, and before he had time to finish Sam was upon him again, this time pressing their lips together in one hot, wet collision. One hand reached up behind Cas' neck and the other pressed into his ever-hardening erection again.

Cas tried to speak between their parted lips, but a barely intelligible "Sam" was all he could muster.

Cas touched everywhere, all over Sam, going on basic instinct and from what he remembered from being human. This was his favorite part about it, he reminisced; being close to another body, feeling his muscles turn lax, feeling that shiver creeping up his spine and exploding on a thousand tiny nerve endings. One of the things he found most intriguing was kissing. How the wetness and tenderness of the interior flesh of the human mouth caused an increase in the speed of his pulse and a damp heat to spill from his groin. Sam's mouth was very different to April's. After all, Sam was a human. And male. He felt different. Warmer. More sturdy in his arms, however, it seemed, less sure of himself. Cas enjoyed the way his tongue slotted through his parted lips and the way Sam would occasionally groan and nip at his lower lip. But the way that his hands just kept moving and kept _touching_ was unlike anything Cas had ever felt. Even though within himself he knew he wasn't human, shouldn't be a part of this, his vessel still was and because of that he still got painfully,  sinfully, incredibly "turned on" or so it was called.

Sam took him by the elbows to stand at the foot of the bed. The blue light contrasted shadows here and there across his face, across his cheeks under his eyes and over his swollen lips, glistening and right there, ready to be kissed again. His hair was untidy where Cas' hands had been stroking through, and his cheeks were flush. The same cheeks that would stain with tears whenever the younger Winchester had a nightmare. Or perhaps when he discovered some of his nightmares were not just in his head. The same cheeks a thumb would drag over, the thumb of an older brother, to dry them. When Cas made no move, Sam fumbled at the buttons of his shirt, knuckles brushing against his collarbone.

The shirt fell to the ground, and Sam slid his hands up smooth forearms.

"What's that face for?" Sam whispered, leaning into him.

"Dean..." Cas said, looking somewhere behind Sam.

Sam made a low noise deep in his throat. Contemplated his words. "What about him?"

"I don't think... He would allow this."

"Well," Sam started, and as if it was an act of defiance in itself, stripped out of his shirt and pants. "Dean's not the one who gets to make decisions for me anymore."

Cas stared in fascination at the boy who had become a man. Miles of flawless curves and ripples, smooth skin stretched taut over firm muscle. The perfect exemplification of the male form, as it been fabricated at the dawn of mankind by the hand of God himself.

And for the first time since coming down to Earth, Cas understood. Really understood. _What_ exactly he understood, well, that was a different story. Maybe humanity. Maybe just sex. But whatever it was, he seemed to be struck with a newfound curiosity as he led Sam on to the bed.

Sam writhed under him, hands on Cas' hips eagerly rubbing, and from there it all happened too fast. Cas was stripping out of his pants and boxers and sliding Sam's off in an almost-trance. He dragged the backs of his fingers down soft, hot thighs and then pushed one of them up gently, slowly.

Cas didn't really understand the concept of "preparing" the muscle before penetration - just moved off the basic primal instinct of sex and the actual theory of it, so when he started to move inside him, Sam felt lightheaded. Sam's eyes fluttered shut and he gripped one of Cas' shoulders for leverage or just for something to squeeze.

Sam groaned as Cas inched in and his hands jumped down in an unconscious gesture of self-protectiveness. "Wait, Cas..."

"Is this alright?" Cas asked, shaky, concerned. He really had no idea.

"Just... Just go a little slower..."

"Right. Sorry..."

And it hurt like hell, actually pretty similar to the burning sensation of the needle Cas was jabbing into his neck earlier today, but Sam didn't particularly mind. Actually, call him masochistic, but he maybe kind of enjoyed it. Because it meant that he was _feeling_ something all on his own. And he could care less about what Dean would have to say about this. If Dean ever found out about this. Not that he had to. And _oh,_ fuck. Why was he, _fuck,_ why was he thinking about Dean?

Cas found it easier if he leaned forward and pressed his palms down on the bed on either side of Sam's shoulders. It was hard to move inside Sam at first, the fit was really tight. So tight, in fact, that he briefly wondered if he was doing it correctly. But once he kept up with the motion and as he picked up the pace a little, it came easier. He read Sam's noises as signs of his pleasure and discomfort throughout the whole process. If he went in too deep too fast, a choked off moan would escape his mouth followed by a quivering bottom lip and an attempt to steady his own breathing, so Cas took that as something particularly painful. On the contrary, if he angled his thrusts a little more _that_ way, a different kind of moan came out of him; higher, and Sam would clutch at his back and scrunch his eyes shut momentarily.

He was quite a vision. Breathing so heavily into his mouth, glowing blue and dewy with a thin film of sweat, clutching on to him and occasionally arching backwards.

The friction was too much, too good, and Cas felt like his body was on fire, climbing higher and higher, chasing some sort of supreme euphoria. Sam reached down to touch himself and was now letting out a constant litany of hastened pants on every exhale.

"Am I hurting you?" Cas whispered, because he just needed to be sure. He could feel Sam tightening around him.

"No, keep going," Sam urged him on so quickly it all came out more like one word than three, and then Cas slid in all the way again. He knew it was impossible but he just wanted to go further in, deeper, get _more._ "Please..." He suddenly felt way too big for the skin he was in, and momentarily feared he might actually _come out_ of it, but he couldn't bring himself to hold on to one thought long enough to care.

Sam groaned from under him, uttered a few curses along with several words of encouragement, and Cas could tell that he was rising too, almost there...

And Sam could swear the ground was shaking, in fact he almost heard it, low like a rumble but vibrating like a passing train, and he saw stars. His come shot out of him with every pulse, every thrust of Cas' erratic hips, and it was at the same moment that he heard Cas cry out above him, raspy and guttural and choked off. It seemed to rival the trembling walls. Sam could feel himself filling up. It felt both strangely foreign and really, really amazing.

As he tried to catch his breath, Cas almost collapsed on top of him, dropping his head down to his neck to rest there. His chest brushed against the wet splotches that stretched all the way up his front.

The tremors finally died down, Cas catching his breath enough to pull back a little and look at Sam. They both seemed to be wearing the same dazed expression.

"I never..." Cas said quietly, between pants, "I never thought it could feel that good."

Sam blinked long and slow, letting his eyes rest shut for a few seconds, and smiled feebly. Then Cas finally rolled off of him, and Sam just started to feel wet and cold and fucked out and yeah, sore.

"Just... Don't tell Dean, okay?"


End file.
